The configuration of the transport network is important for the efficient operation of the transport system. It significantly affects the cost of transportation and their reliability. The construction of each individual element of the network is the implementation of a very specific solution, but the overall development of the network largely manifests internal patterns. One approach to studying such patterns is to model the natural development of the transport network. This paper proposes a formalization of various approaches to modeling the natural development of networks and identifies strict relationships between the approaches under consideration.

Keywords: transport network modeling, dynamical model, stationary model, the configuration of the transport network, transport network topology

This paper considers basic element of device of energy storage which is a piezoelectric generator (PEG) of cylindrical form with the attached inertial mass. A finite element modeling of the device operation is carried out during active load in the external circuit. The main purpose of the operation is to compare the output potential and frequency characteristics of the device known in the literature models of systems with concentrated parameters. On the basis of these models, we can receive the analytical dependence of parameters of PEG with its geometric characteristics and mechanical properties of the used materials. However, the question of the range of applicability of these formulas is still open. In this paper, based on the numerical analysis of finite element models of PEG in package ANSYS, we obtained comparison with the analytical formulas that show the values of some parameters of simplified models and set the boundaries of their applicability.

Keywords: energy storage, PEG, piezoceramics, effective mass, resonant frequency, FEM

Cold asfaltobetonny mixes which unlike standard mixes prepare without drying and heating of a mineral component are developed. Advantages of these mixes are that they is better, than standard mixes cooperate with a damp repaired covering and in the course of warehousing don't demand performance of actions for prevention of caking of a mix. Mixes are intended for timely localization of the centers of the destruction appearing on pavings in the early spring and autumn.

Keywords: emergency repair of pavings, hollows and sags, surface-active substances, razzhizhenny bitumen, cold asfaltobetonny mix.

Information about authors of issue №3 (2010)

Keywords: authors